This invention relates to piston pumps and compressors, and more particularly to a method of assembling the unit as a reliable and robust package, maintaining a low cost and easily assembled configuration.
Small-scale air compressors are often used to power nebulizers. A typical type of compressor for that purpose uses a wobble piston. Examples of such compressors are found in U.S. Pat. No. 3,961,868, issued Jun. 8, 1976 to Arthur J. Droege, Sr. et al, for "Air Compressor" and U.S. Pat. No. 4,842,498, issued Jun. 27, 1989 to Roy J. Rozek, for "Diaphragm Compressor".
In a typical compressor, a piston reciprocates in a cylinder sleeve to compress air. The piston is a plastic connecting rod having a piston end disposed in the cylinder sleeve, and a connecting end connected to an eccentric metal pin mounted to a shaft. As the shaft rotates, the connecting rod having a piston head disposed in a cylinder sleeve reciprocates to compress air. A valve head member in fluid communication with the cylinder sleeve feeds air into the cylinder through an intake port, and provides an escape for compressed air through an exhaust port, and ultimately to an outlet in the valve head member.
Typical compressor assemblies include a compressor housing fastened securely to the motor. A cylinder sleeve rests on the housing to accurately position the cylinder sleeve and corresponding valve plate at a fixed position relative to the motor shaft. The valve head member is routinely positioned on top of the cylinder sleeve, with a sealing gasket squeezed between the valve head member and cylinder sleeve. The valve head member is typically fastened in the position above the cylinder sleeve by screw type fasteners that project down into the housing. This type of configuration is normally complicated to assemble, and the gasket between the valve head member and cylinder sleeve is sometimes unreliable due to component tolerances and variations in the fasteners assembly. Therefore a need exists for a robust compressor that provides a reliable seal between component pales, yet is economical to produce and assemble.